Freshwater Nano Aquarium – The Beauty of Small

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Welcome to the world of freshwater nano aquariums, where small fish tanks are creating a big buzz among fish keepers!

These compact setups have attracted a whole new audience to the fascinating hobby of fish keeping.

While nano tanks may seem foolproof due to their size and convenience, it’s essential to consider a few factors before diving in.

Maintaining a small system comes with its own set of challenges, but with the right knowledge and approach, you can ensure the survival and success of your freshwater nano aquarium.

What is a Nano Aquarium?

In essence, a freshwater nano aquarium is a small-scale aquarium that typically holds around 1 to 10 gallons of water.

Despite their compact size, these tanks can provide an enchanting glimpse into the underwater kingdom.

The primary benefit of a nano fish tank is its space efficiency.

Whether you live in a cozy apartment, have limited surface area, or simply prefer a more modest setup, a nano tank can fit seamlessly into any nook or cranny.

Their compact nature allows for easy placement on a desk, stand, or countertop, letting you enjoy the beauty of your fish tank without compromising on your living space.

Furthermore, nano tanks offer a unique opportunity for creativity and customization.

With limited space to work with, you can focus on creating a breathtakingly intricate aquascape by carefully selecting rocks, plants, and ornaments to craft a miniature underwater paradise.

These small-scale setups are ideal for showcasing delicate and visually striking species, such as vibrant shrimp or tiny, colorful fish like celestial pearl danios or sparkling gouramis.

The possibilities for creating a captivating microcosm are virtually limitless!

Nano Aquarium Benefits

Basics of Nano Aquariums

Many of the nano aquariums available on the market come as convenient kits that include lighting and filtration systems.

While these kits provide an easy entry point for new hobbyists, they may not meet the needs of experienced aquarists who want to explore the nano trend.

Some kits may not provide sufficient lighting for a planted tank, and as you may know, plants and nanos go hand in hand, especially in freshwater setups.

However, there are kits specifically designed for planted tanks, making them a better choice for seasoned hobbyists.

If you’re considering a planted freshwater setup, you might find that nano marine aquarium kits can also be a fantastic option.

These kits typically include integrated filtration and higher-quality lighting, which can be ideal for your planted nano tank.

Contrary to common myth, actinic lighting is not harmful to freshwater plants.

In fact, scientific evidence shows that they benefit from the wavelengths in the actinic range.

If the lighting can sustain corals, it will certainly support your plants too.

While kits are a great starting point, especially for beginners, more experienced hobbyists may prefer to choose individual tanks sold separately.

Several companies offer a range of sizes, including deep cube-shaped tanks that work wonderfully for freshwater setups like ours.

Setup & Maintenance


The most important piece of equipment for your nano tank will be the filter.

Nano tanks are notorious when it comes to shifting water quality as parameters can change rapidly due to the small water volume.

Choose a filter that is suitable for your nano aquarium size and follow a weekly maintenance regime that includes cleaning the filter media to keep it functioning at its optimal level.

Another factor is the placement of your tank.

It’s best to avoid exposing it to cold drafts or direct sunlight, as these can significantly affect the water temperature.

Cold drafts can cause the water to cool down the whole time and the heater will be constantly turned on in an attempt to raise the temperature.

Direct sunlight will not only cause unsightly algae but it will also heat the water and you could potentially end up boiling the tank inhabitants.

Lastly, ensure that your nano aquarium is level and well-supported.

A dedicated stand or sturdy piece of furniture will do the trick.


Maintaining water quality in these smaller tanks can be more challenging compared to larger aquariums.

The reduced water volume means that changes in temperature, pH levels, and ammonia concentrations can occur more rapidly.

Consequently, it’s crucial to monitor and manage water parameters diligently.

Performing regular water changes and ensuring the filtration system is suitable for the tank size is an important aspect of nano aquariums.

Due to the increased sensitivity of nano tanks to water conditions, they may not be the best choice for beginner fish keepers.

Novices often benefit from starting with larger tanks, as they offer a more forgiving environment for learning the ropes of aquarium maintenance.

However, with some patience, research, and dedication, even those new to the hobby can successfully care for a nano tank.

Perform water changes at least once a week, or even more frequently if possible.

Use a siphon to remove any detritus from the bottom of the tank.

While some aquarists prefer not to disturb the substrate in planted tanks, I recommend lightly vacuuming the top layer to prevent the buildup of organic waste, which can cause problems over time.

Monitor the water temperature during water changes and adjust the new water to match the aquarium’s temperature.

Large temperature shifts due to the addition of hot or cold water can be detrimental to the well-being of your aquatic inhabitants.

Rinse the filter material in the old tank water so as not to destroy the beneficial bacteria. Never use fresh water.

When it comes to lighting, remember that it can make or break any aquarium, and the right choice is even more crucial for nano tanks.

Avoid light sources that generate excessive heat.

LED lighting is generally the best option.

There’s a wide range of LED fixtures available, many of which can be customized for light intensity and spectral output.

The specific light spectrum and intensity you choose will depend on the type of flora and fauna you plan to keep in your tank.

Benefits of a Nano Aquarium

Here are some of the benefits of owning a nano aquarium:

Initial Setup is More Affordable

Setting up a nano aquarium is less expensive compared to larger aquariums.

You can get a complete kit that includes everything you need to start your aquarium for a reasonable price.

They also require less decor, substrate, and plants helping those fish keepers that are on a tight budget.

Suitable for Small Areas

Nano aquariums are perfect for small apartments, offices, or spaces where larger aquariums cannot fit.

You can place them on a desk, countertop, or table, and they will add a touch of beauty to your living or workspace.

Easier to Move Around

One of the biggest advantages of a nano aquarium is its portability.

You can easily move it from one room to another or take it with you when you move to a new place.

This is especially useful for people who like to rearrange their furniture or move frequently.

Quick Water Changes

Nano aquariums have less water volume, which means water changes are quicker and easier.

You can change the water in your nano aquarium in just a few minutes, which is a significant time saver compared to larger aquariums.


A nano aquarium is an excellent choice for anyone who wants to enjoy the beauty of fishkeeping without the high cost and maintenance of larger aquariums.

With its affordability, portability, and ease of maintenance, a nano aquarium is a great way to bring some aquatic life into your home or office.

Disadvantages of a Nano Tank

If you are considering a nano fish tank, you need to know that there are some disadvantages to these smaller aquariums.

Here are a few things to keep in mind:

Water Conditions Are Not as Stable

Because of the small size of a nano tank, water conditions can fluctuate more easily than in larger tanks.

This means that you will need to monitor the water quality more frequently and make adjustments as necessary.

Regular water changes and testing are a must to ensure that your fish and other inhabitants stay healthy.

Limitation of Tank Inhabitants

Another disadvantage of a nano tank is that there are limitations on what you can put in it.

You will need to choose fish and other inhabitants that are appropriate for the size of your tank.

This means that you may not be able to keep some of the larger or more exotic species that you might be interested in.

Research the needs of any species that you plan to keep and ensure that they will thrive in a nano tank environment.

More Frequent Maintenance

Finally, nano tanks require more frequent maintenance than larger aquariums.

This is because the smaller volume of water means that waste products can build up more quickly.

You will need to perform more frequent water changes and cleanings to keep the tank healthy.


While there are some disadvantages to a nano tank, the benefits outweigh these challenges.

With careful planning and maintenance, a nano tank can be a beautiful and rewarding addition to your home or office.

Plants for Nano Tank

Nano Plants

Nano tanks are perfect for creating microhabitats, and you have a variety of plant options to consider.

Most bunch or stem plants can be successfully maintained in a nano tank, although fast-growing ones will require more frequent pruning.

This group offers a diverse selection of shapes and colors, which can add visual interest to your nano tank.

These plants are typically best suited for background or midground placement.

Here are a few popular choices: Mayaca fluviatilis, Hemianthus micranthemoides, Alternanthera reineckii “Lilacina,” Bacopa monnieri, Rotala indica, and various Ludwigia species.

If you’re looking to create a lush foreground, consider plants from the Cryptocoryne genus.

Many of these plants will gradually spread and fill in the area with dense growth.

Some of my favorites include Cryptocoryne beckettii, C. beckettii var. “petchii,” C. affinis, C. pygmaea, C. nevillii, and the various forms of C. wendtii.

For a “lawn” effect, you can try Echinodorus tenellus, dwarf Sagittaria species, or Glossostigma elatinoides.

Another interesting choice for the foreground is Marsilea crenata, which resembles a four-leaf clover.

Smaller species of Nymphaea, such as Nymphaea rubra and N. micrantha, can serve as striking focal points or float gracefully on the water’s surface.

Additionally, smaller Anubias species like Anubias barteri var. “nana” or “nana petite” can be particularly effective.

To keep your plants healthy in a freshwater nano tank, it’s important to provide them with proper fertilization.

I recommend dosing plant fertilizers on a daily basis to keep the system nutrient-poor, similar to how reef hobbyists manage their systems.

While most plant fertilizer bottles suggest weekly or biweekly dosing, this can lead to an excess of nutrients that fuel algae growth.

To avoid this, divide the recommended weekly dosage by seven and dose that amount each day.

By following this approach, your plants will outcompete algae for nutrients, helping to control algae growth.

Adjust the dosage based on the specific needs of your tank, whether it’s heavily or lightly planted.

Nano aquarium fish

Nano Fish

You’ll be pleased to know that many species thrive in small aquariums.

One genus worth exploring is Boraras, as all Boraras species make excellent choices.

One standout species is Boraras brigittae, commonly known as the chili or mosquito rasbora.

With its vibrant orange pattern, this fish is a true gem that adds a radiant touch to any planted aquarium.

Another fantastic option is the Galaxy Danio (Danio margaritatus), known for its stunning colors and pearl-like spots.

The cichlid family offers several species that adapt well to small aquariums. Apistogramma, with its 200-plus members, provides numerous suitable choices.

Consider Apistogramma agassizii and A. cacatuoides, along with their geographic variants and captive-bred color morphs, as they make wonderful additions to freshwater nano tanks.

Livebearer enthusiasts have a variety of options for planted tanks.

Endler’s livebearers (Poecilia wingei) are a popular choice, while more advanced hobbyists may enjoy the challenge of keeping Micropoecilia species in their nano setups.

When it comes to killifish, most species, except the largest ones, can thrive in community or biotope nano tanks with suitable tankmates.

However, be mindful of long-finned species, as they may be targets for other fish.

Ensure your tank has a tight-fitting cover to keep the killifish safely inside.

One beloved fish that should not be overlooked is the Betta splendens, also known as the Siamese fighting fish.

You can choose a single Betta specimen in any finnage type and color that captures your interest.

No aquarium is complete without some delightful bottom-dwelling species, and that’s where Corydoras catfish come in.

The genus Corydoras offers a range of choices, with the smallest species being perfect for nano tanks.

Consider Corydoras pygmaeus, C. hastatus, and C. habrosus as great options.

If you’re open to slightly larger catfish, don’t forget about C. panda and the rare but incredibly cool C. gracilis.

Nano Aquarium shrimp

Nano Aquarium Invertebrates

Shrimp add an extra touch of charm to nano tanks, and luckily, there are many suitable species available.

However, take care to ensure that your chosen shrimp will not be preyed upon by the fish in your tank.

While some predation on shrimp juveniles is almost inevitable, they reproduce quickly enough to compensate for any losses.

Cherry shrimp (Neocaridina davidi) in their various color morphs are a wonderful choice and widely available.

Crystal shrimp (Caridina cantonensis) and their morphs are also popular.

Just remember not to mix different color morphs of the same shrimp species, as crossbreeding may result in offspring of poor quality and color.

If you’re looking for an intriguing invertebrate option, consider the Mexican dwarf crayfish (Cambarellus patzcuarensis).

These little creatures are plant and fish-friendly, and they only grow to about 2 inches (5 cm) in size.

However, be sure to check if there are any restrictions on crayfish sales in your area, as the C. patzcuarensis species is considered endangered.

For snail enthusiasts, members of the Neritina genus are your best bet.

Keep in mind that Neritina snails require brackish water for successful reproduction.

The zebra nerite snail (Neritina natalensis) is a personal favorite.

Feeding Tips

Remember one important rule: don’t overfeed your fish.

Due to the smaller water volume in nano tanks, it’s crucial to provide only the highest quality food and offer it sparingly.

Disregard the instructions on flake or pellet containers and feed only the amount that can be consumed within 60 seconds.

Feed several times a day if you wish, but always control the portion sizes to prevent uneaten food from causing issues in the tank.

However, if you opt for algae wafers or gel-based diets intended to be consumed over a longer period, this rule doesn’t apply.

Wrapping Things Up

A nano fish tank can be a fantastic choice for fish enthusiasts who are short on space but big on passion.

These compact aquariums offer a multitude of benefits, from their space efficiency and versatility in aquascaping to the enchanting array of small and colorful aquatic species they can host.

However, it’s crucial to acknowledge the potential challenges they present in terms of maintaining water quality.

If you’re a beginner, you might want to consider starting with a larger tank.

Remember, no matter the size of your aquatic adventure, with dedication and care, your nano tank can become a captivating underwater oasis that brings joy and tranquility to your living space.

Photo of author


Irma Bense is the founder of She has over 42 years of experience in keeping fish.She has kept both freshwater and saltwater fish through the years.She has extensive knowledge in breeding numerous species of fish from Show Guppies, Cory Catfish, German Blue Rams to Apistogrammas.You can learn more about Irma on the 'About' page.

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